OpenStack Compute (Nova)

Upgrade with minimal downtime

Registered by John Garbutt on 2011-09-28

Clouds are expected to be always available and involve large numbers of servers. This blueprint looks how we can perform upgrades with minimal disruption.

Goals for the upgrade are:
- where possible, transparent to the cloud users
- minimal instance downtime or instance connectivity loss
- ability to rollback to a pre-upgrade state if things fail
- ability to upgrade from v2 to v4 without having to do upgrade to v3 first (supporting at least two versions forward/back?)
- define what we mean by v2 and v4. It could mean 2012.1 -> 2012.3 (etc.), but what about sprint releases, what about bug fix releases to major versions (http://summit.openstack.org/sessions/view/106)

Blueprint information

Status:
Complete
Approver:
Vish Ishaya
Priority:
High
Drafter:
Citrix OpenStack development team
Direction:
Approved
Assignee:
Nova Upgrades Team
Definition:
Obsolete
Series goal:
None
Implementation:
Unknown
Milestone target:
None
Completed by
Vish Ishaya on 2012-05-17

Related branches

Sprints

Whiteboard

This needs to be broken out into concrete steps and blueprints by the upgrades team --Vish

(?)

Work Items

Dependency tree

* Blueprints in grey have been implemented.